Cécile McLorin Salvant makes it all sound not effortless exactly, but sorta easy. You get the strong impression she’s having a blast. In a way, that ease of execution is a problem — it creates the temptation to top herself, and go for the Extra Big Moments, like the killer high-note ending of “What a Little Moonlight Can Do.” It makes sense that she’d exploit her extreme highs and lows; she won’t be able to reach them forever. And age tends to calm folks down, so the over-exuberance may take care of itself. My point is this: She doesn’t need to try to knock us out. We’re already knocked out.